Hoarau lands French Cup for PSG
The 26-year-old Hoarau, from Saint Louis on La Reunion island in the Indian Ocean, struck seconds before the turnaround in the final half hour to add some gloss to what has been a poor season for the capital club.
After a largely turgid affair, veteran Claude Makelele fed Christophe Jallet on the right and although Monaco keeper Stephane Ruffier parried the effort, Hoarau snapped up the rebound.
With a place in the Europa League at stake, both sides had every reason to go for the jugular - particularly as neither club has shone in the league this season with both mired in mid-table.
PSG had the lion's share of the first half possession and Ludovic Giuly, Mevlut Erding and Mamadou Sakho all missed half-chances as Monaco - who did the double over PSG in the league this term - elected to soak up the pressure.
The Parisians last lifted the trophy in 2006 whereas their rivals won their fifth and most recent pot back in 1991. Though outnumbered, the principality side did have Prince Albert among their 7,000-strong travelling contingent for the showdown in the capital.
The Monegasques swiftly showed their steely side when Argentine Alejandro Alonso was booked on 22 minutes for elbowing the marauding Stephane Sessegnon. The southerners were slowly coming out of their defensive shell and in the 27th minute busy Korea Republic favourite Park Chu Young won a free kick on the edge of the box but Brazilian Nene was unable to shake off the attentions of Jallet.
Two minutes earlier, Turkish star Erding thought he had put PSG in front, swivelling and firing home but he was caught offside. The striker then appealed for a spot-kick eight minutes after the restart after being bundled over but his plea fell on deaf ears. At the other end Nene then combined well with Colombian Juan Pablo Pino, who wriggled through a clutch of defenders only to shoot too close to PSG's Cameroonian keeper Apoula Edel.
PSG tried to inject some fresh legs in the shape of veteran forward Peguy Luyindula, who came on for Giuly with 13 minutes of normal time remaining while Monaco made their own change in throwing on Niger striker Ouwo Moussa Maazou for the impressive but tiring Pino in the 86th minute. Erding should have won it in the 90 minutes but with just keeper Ruffier to beat he drove his effort against the bar.
Then came Hoarau's decisive intervention marred only slightly for a booking picked up in the closing stages for a foul on Eduardo Costa as the encounter meandered to a conclusion.